JPS59152334A - Conversion of hydrocarbons - Google Patents

Abstract

PURPOSE:Aliphatic hydrocarbons are brought into contact with a zeolite catalyst which is ion-exchanged with Cu, Zn or Cr and has high activity and duration to produce aromatic hydrocarbons ranging within gasoine boiling point in high selectivity. CONSTITUTION:A hydrocarbon mixture containing 1-10C paraffins such as light naphtha is brought into contact with a zeolite catalyst which is ion-exchanged with Cu, An or Cr at 300-700 deg.C under pressure over 100 atmospheric pressure to give a hydrocarbon mixture containing aromatic hydrocarbons such as gasoline. The catalyst is prepared by dipping a zeolite in an aqueous solution of a Cu, Zn or Cr compound at 80-100 deg.C for 3hr to 1 week to effect ion exchange, followed by filtration, drying and roasting. The amount of ion-exchanged metal is preferably 0.5-10wt% based on the zeolite.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for converting aliphatic hydrocarbons to aromatic hydrocarbons.

More specifically, Fr-R is a method for producing a hydrocarbon mixture containing aromatic hydrocarbons using a hydrocarbon mixture containing paraffins having 1 to 10 carbon atoms as a raw material, and includes one or more of copper, zinc, and chromium. This invention relates to a method for obtaining aromatic and flaming hydrogen at a high conversion rate and high selectivity using a zeolite catalyst with ion-exchanged metals.

Mixtures of aromatic hydrocarbons are widely used as raw materials for gasoline or the chemical industry. In general, they can be obtained by distillation of petroleum or by conversion of heavier petroleum fractions, such as catalytic cracking, thermal cracking. In order to improve the octane number of the hydrocarbon mixture thus obtained, methods are often used to catalytically reform the carbon content to increase the aromatic content.

It has been well known that crystalline aluminosilicate zeolite catalysts have traditionally been used in reforming and conversion reactions of petroleum fractions. A number of patent applications have been proposed (U.S. Pat. Nos. 3,140,249, 3,140,251, 3,140,253, etc.) for decomposing products into low molecular weight products and for improving the octane number of hydrocarbon mixtures.
No. 3400072, each specification, etc.).

The present invention does not relate to the above-mentioned general hydrocarbon conversion method (rather, the present invention relates to aliphatic hydrocarbons, i.e., paraffins having 1 to 10 carbon atoms, obtained by distillation, thermal decomposition reactions, etc.).
The present invention relates to a method for producing aromatic hydrocarbon mixtures useful as gasoline components from olefin-containing hydrocarbons.

Conventionally, the above-mentioned zeolite catalyst has been widely used as a catalyst for converting such aliphatic hydrocarbons into aromatic hydrocarbons having a boiling point range.An example of a proposal regarding this is Japanese Patent Publication No. 56-42639. and so on.

However, these catalysts, for which patent applications have already been filed, have the problem of low yields of aromatic hydrocarbons (and short catalyst life).

The present inventors have solved the above-mentioned problems of the prior art (as a result of extensive experimental studies, it has been found that zeolite ion-exchanged with one or more metals of copper, zinc, and chromium has the aromatic properties of the aliphatic hydrocarbons). We have discovered the groundbreaking fact that this catalyst is extremely effective as a catalyst for conversion reactions to group hydrocarbons, and has significantly improved activity, selectivity, and durability compared to conventional catalysts. , the present invention has been achieved.

That is, the present invention is directed to a method for producing an aromatic hydrocarbon mixture using a hydrocarbon mixture containing paraffins having 1 to 10 carbon atoms as a raw material. The raw materials were heated to a reaction temperature of 300
It is characterized by bringing one or more metals of copper, zinc, and chromium into contact with an ion-exchanged zeolite catalyst under conditions of ~700℃ and a reaction pressure of 100 atm or less, and produces aromatic hydrocarbons in high yield. The present invention provides a method for manufacturing.

The hydrocarbon mixture containing paraffins having 1 to 10 carbon atoms as used in the present invention may be paraffin alone or a mixture containing olefins, naphthenes, aromatic hydrocarbons, etc., and has a boiling point range of about 100. Light naphtha or the like having a temperature below ℃ can be preferably used as the raw material.

In addition, the hydrocarbon mixture containing aromatic hydrocarbons as used in the present invention refers to a hydrocarbon mixture containing 1% by weight or more of aromatic hydrocarbons, and a mixture containing other paraffins, olefins, or naphthenes.

The reaction temperature of the present invention is 500 to 700"C, preferably 4
00 to 600°C, and the reaction pressure is below 10,081 boiling points, preferably below 50 atzo.

The reaction temperature is limited to 300-700C.
i. At temperatures below 300℃, most of the paraffin reacts.
This is also because the ratio of the cogging reaction and the decomposition reaction to methane (R4) increases at temperatures above 700''C, resulting in a short catalyst life.

The reason why the reaction pressure is limited to 10 Q atm or less is because
This is because the equilibrium conversion rate of the conversion reaction of aliphatic hydrocarbons to aromatic hydrocarbons becomes smaller at high pressures, and there is no advantage in increasing the pressure above 100 a1;m.

Moreover, the zeolite referred to in the present invention refers to a zeolite having a pore size of 3 to 15A and having a structure similar to or similar to zeolite, and the following zeolites are used as examples.

(1) A-type zeolite (ii) Y-type or Y-type zeolite
) (110 mordenite or modified mordenite\4V] Natural zeolite (erionite, clinoptilolite, etc.) (y) ZSM- with a SiO, /At, O, ratio of 12 or more
5 type zeolite (%Koshō 46-10064.53-
23280, JP-A-50-54598.51-6729
8.52-43800.115800.54-5269
9.99799.107499.137500.151
600.55-1j6619.121912.56-9
212.92114 Publication Basket] ■ Crystalline silicate (Japanese Patent Publication No. 56-40084, Japanese Patent Publication No. 55-7598.76825.16241?, 56-22625.59619.967
19.57-10684.190084.197227
The zeolite catalyst in which one or more metals of copper, zinc, and chromium are ion-exchanged can be prepared by using a known ion-exchange technique. Specifically, zeolite is immersed in an aqueous solution of one or more compounds of copper, zinc, and chromium, such as chlorides and nitrates.
A method of ion exchange treatment at ~100° C. for 3 hours to 21 weeks, followed by filtration, drying, and baking is used.

In addition, the ratio of ion-exchanged metal to zeolite is 0.1 to 20% by weight, preferably [7 (is 0
5 to 10 percent by weight is most commonly used.

The catalyst, which was scooped out at 3 kCL, was used for the reaction to produce an aromatic hydrocarbon mixture from a hydrocarbon mixture containing puffins of C3 to C1o, as shown in the following examples. This catalyst exhibits high selectivity and four essential properties not found in conventional catalysts.

Hereinafter, the present invention will be specifically explained with reference to Examples.

Example 1 Y-type zeolite with a particle size of 2 to 4 (NH4-Y-type zeolite called 5K-41 manufactured by Union Carbide, calcined at 300'0, referred to as comparative catalyst 1)
Catalysts 1 and 2.3 were crushed in an aqueous solution of copper nitrate, zinc nitrate, or chromium nitrate, treated with IDD'O for 6 hours, and ion-exchanged with 2 weight percent each of copper, zinc, and chromium.
was prepared.

The experiments were carried out using these catalysts under the conditions shown in Table 1, and the results are shown in Table 2.

In Table 2 below, aromatic selectivity refers to the proportion (weight percent) of aromatic hydrocarbons in the produced hydrocarbons.

Example 2 Catalyst 4 was prepared by ion-exchanging copper and zinc by 1% by weight using Y-type zeolite in the same manner as in Example 1.
Catalyst 5 was prepared by ion-exchanging 1 weight percent each of zinc and chromium, and Catalyst 6 was prepared by ion-exchanging 1 weight percent each of copper and chromium.

Using these catalysts (execution was carried out under the same conditions as in Example 10 Table 1, and the results are shown in Table 3).

Example 5 Catalyst 7 was prepared by ion-exchanging copper and zinc by 1% by weight each using H-type mordenite (Zeolon 900H1 Comparative Catalyst 2 manufactured by Two-Tone) with a particle size of 2 to 4cm in the same manner as in Example 2. , Catalyst 8 in which 1 weight percent each of zinc and chromium were ion-exchanged, and Catalyst 9 in which 1 weight percent each of copper and chromium were ion-exchanged.

Using these catalysts, the experiment was carried out under the same conditions as in Example 10 Table 1, and the results are shown in Table 4.

Example 4 Z, SM-5 type zeolite was placed in the following manner. Water glass, aluminum sulfate, sodium hydroxide, water 36 Na, 0-A, l:, O, -80Sin,
・Mixed to a molar ratio of 1600 H, 0, added appropriate amount of body acid to make the pH of the above mixture around 9, organically converted, and added tetrapropylammonium bromide as a metal to Alx Add 20 times the number of moles of Os, mix well, and place in a 500cc stainless steel autoclave VC.
I staked out.

The above mixture was reacted at 160'O for 3 days with stirring at about 500 rllllTl. After cooling, the solid content was filtered and washed, dried at +10-0 for 12 hours,
Baked for 6 hours at 'Q.

The crystal grain size of this product is around 1μ, and the composition excluding organic compounds is 0.5 Na2O-A7. O,・8OSin.

Met. The X-ray diffraction pattern of the powder C shows the time II/,
(ZSM-5 described in Publication No. 46-10064
It was the same as type zeolite.

This zeolite was immersed in 1N hydrochloric acid and treated at 80°C for 5 days. This was washed, dried at 110°C for 12 hours, and calcined at 550°C to prepare H-ZSM-5 (comparative catalyst 3).

Catalyst 10 was prepared by ion-exchanging 2 weight percent each of copper, zinc, or chromium in the same manner as in Example 1 using this H-Z SM = 5 molded to a particle size of 2 to 4 cm.
, 11.12 was prepared.

Using these catalysts, the experiment was carried out under the same conditions as in Example 10 Table 1, and the results are shown in Table 5.

Example 5 The m-zs'n-s prepared in Example 4 was molded into a particle size of 2 to 4 mm, and copper and zinc were ion-exchanged by the same method as in Example 2 at a concentration of 1% by weight each. Catalyst 16, ion-exchanged catalyst 14 with 1Ai each of zinc and chromium, 1i each of copper and chromium', r! Each percent ion-exchanged catalyst 15 was prepared.

Using these catalysts, the experiment was carried out under the same conditions as in Example 10 Table 1, and the results are shown in Table 6.

Example 6 Crystalline silicate was synthesized as follows.

Prepare water glass, sodium hydroxide, and water so that the molar ratio is 36 Na, O-80Sin, -1600H,0, and add an appropriate amount of sulfuric acid to this so that the pH of the above mixture becomes around 9. A crystalline silicate was prepared using the same method as in Example 4. This crystalline silicate molded with a particle size of 2 to 4 trmK is immersed in an aqueous solution of steel nitrate, zinc nitrate, or chromium nitrate, and treated at 100'0 for 6 hours to ionize 1% by weight each of copper, zinc, or chromium. Replaced catalyst 1
6, 17.18! 4 were made.

The experiment was carried out using these catalysts under the same conditions as in Table 1 of Example 1, and the results are shown in Table 7.

Example 7 The reaction was carried out using Catalyst 12 under the same conditions as in Table 1 except that the reaction temperature was changed. The results are shown in Table 8.

Table 8 Example 8 The reaction was carried out using Catalyst 19 under the same conditions as in Table 1 except that the reaction pressure was changed. The results are shown in Table 9.

Table 9゜Example 9 The experiment was carried out using Catalyst 12 under the same conditions as in Table 1 except that the raw materials were changed. The results are shown in Table 10.

Here, the light naphtha includes about 40 wt% pentane, -xane about 50 wt%, and about 10 wt% other paraffins.
% composition was used.

In addition, in catalysts 1 to 18 of Examples 1 to 6, 10 to 5 gwt% of C3 to C4 olefins were produced in addition to aromatics. By using the catalyst according to the method of the present invention, it is also possible to produce lower olefins that can be used as raw materials for the chemical industry.

As shown in the examples above, by using the catalyst according to the method of the present invention, a hydrocarbon mixture containing aromatic hydrocarbons can be obtained with high selectivity from a hydrocarbon mixture containing paraffins having 1 to 10 carbon atoms. It also has excellent durability and can be operated for long periods of time.

The examples shown in the j6 embodiments are merely illustrative and limit the present invention.&'1. What (・.

In addition, in Example 16, the results in a fixed bed were shown, but this does not particularly limit the reactor type. , r
(It goes without saying that a quiz reactor such as a fluidized bed or a pneumatic conveyance type may also be used.

Sub-agent: 1) Akira Sub-agent Ryo Hagi Hara -

Claims (1)

[Claims] A method for producing a hydrocarbon mixture containing aromatic hydrocarbons using a hydrocarbon mixture containing paraffins having 1 to 10 carbon atoms as a raw material? The raw materials were heated to a reaction temperature of 300~
A method for converting hydrocarbons, which comprises bringing one or more metals selected from copper, zinc, and chromium into contact with an ion-exchanged zeolite catalyst under conditions of 700° C. and a reaction pressure of 1 or less.